Support for light cutting-wheels.



C. A. PFANSTIEHL.

SUPPORT FOR LIGHT CUTTING WHEELS,

APPLICATION FILED JULY 24, 1916.

CARL A. PFANSTIEHL, OF HIGHLAND PARK PANY, TNC., OF NORTH CHICAGO, ILLI carros.

, ILLINGILS, ASSIGNOE T PFANSTIEHL COM- NOIS, A CORPORATION 0F NEW YORK.

SUPPORTL FOR LIGHT CUTTING-WHEELS.

Specification of Letters Eatent.

Patented May ist, i918..

Application led J'uly 24, 1918. Seal No. 111,051.

To all whom t may concern:

Be it known that I, CARL A. PFANs'rmHL, a citizen of the United States, residing at Highland Park, in the county of Lake and State of Illinois, have invented a certain new and useful Improvement in Supports for Light Cutting-Wheels, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to bearing structures and particularly to a structure adapted to rotate at high speed and one in which vibration must be absolutely eliminated.

The primary use for the structure of my invention is to support composition cutting wheels used for cutting very hard materials such as tungsten rod. The saws or cutting wheels which l have found preferable for use in cutting tungsten contacts from the ends of tungsten rod are composed of vuloanite mixed with an abrasive material such as nely powdered carborundum. I have also found it beneficial to coat the surfaces of the cutting wheels with sodium silicate into which is sprinkled carborundum dust thus giving a glassy external surface to the cutting wheel.

The object of my invention is to provide a cutting wheelsupport which may be rotated at very high speed without any appreciable vibration. Vibration is caused by lack of balance in the rotating parts, and by looseness of the bearings caused either by wear or by expansion of the parts due to heat.

My invention is illustrated in the accompanying drawings in which- Figure 1 is an elevation of my bearing and bearing support; and

Fig. 2 is a longitudinal section.

rThe body of the bearing comprises a cast iron member 1 having a horizontal cylindrical opening through the upper part thereof into which are fitted the end members 2 and 3, the latter being held in place by a plurality of screws 4. The end members 2 and 3 have internal cone faces 6 into which the external races 7 are accurately fitted. The rollers 8 engage the inner faces of theraces 7 and roll upon the outer cone faced surfaces of the cones 10. The rollers 8 are spaced from one another by suitable spacers 12 so formed as to engage the ends of the rollers as well as the sides thereof. The roller bearing itself, including members l8, 9, 10, and 12, forms no part of my invention, these rollers bein of a well-known'make and usedfextensively for automobile bearingsand for other purposes in which the speed of rotation.

is small compared to that at which my device is operated. The rotatable shaft 15 is turned with a pair of cylindrical bars 16 and 17 accurately constructed so as to'iit within the cylindrical openings through the cone members 10 with a forced or drive fit. The central portion 18 of the shaft 15 is enlarged to form a shoulder at 19 against which the right hand bearing cone 10 is forced. The portion of the shaft 15 adjacent the lefthand bearing cone is threaded,` as shown at 22, and carries the internally threaded collar 23 having opposite depressions 24 therein for the reception of a suitable wrench. The members 2 and 3 have projecting external ends 25 and 26 and have a bore somewhat greater than the portion of the shaft extend- 111g therein. The spaces between the inner faces of the parts 25 and 26 and a shaft l5,

are filled with felt washers 27 the pur ose of which is to prevent either caborun um or tungsten dust from working into the bearings, this dust being of such a character that '.5

it would quickly cut the bearings stroy their accuracy.

0n the left end of the shaft 15 is af ulley 30 having a groove therein for g'liiifinga ilat belt. This pully has a cylindrical deand de Y pression in the left end thereof which eX- tends over the protruding portion 25v of the inclosing member 2, thus 'aiding inthe seal- Y ing of the bearing against foreign material from without. 15 is a collar 32 havingv a bore extending over the projection 27 on the inclosing member 3 for the same purpose as formerly described in connection with the bore in the pulley 30. The external face of the collar 32 is accurately turned to form an abutment for the ring 33. The ring 33 and the opposing ring 34 are slightly dished so that when clamped together by means of the nut 35 they engage the cutting wheel 36 more firmly at the periphery of the disks 33 and 34 than at the center. The dish is so slight, however, that when the nut 35 is tightened the greater part of the dish is taken up in the elasticity of the rings 33 and 34. A grease cup 38 is threaded into the top of the member 1 for supplying the cavity in @n the left end of the shaft which the bearings are located with lubricant.

ln the adjustment of this bearing the threaded collar 22 is tightened against the friction of the cone 10 upon the portion i7 of the shaft and the bearings are thus by very, careful adjustment set so that when the plates 2 and 3 are rmly screwed to place the shaft can scarcely be rotated by hand. This adjustment places thebearings under a pressure equivalent to a load of several hundred pounds and eliminates all but the very thinnest iilm of lubricant from between the rollers and their engaging races. During the operation of the device the bearings become quite warm by reason of the heavy load under which they are operating, but the materials of which theshaft 15 and the inclosing member l are constructed have the same co-eliicient oi? eX- pansion and, therefore, the change in temperature does not materially aect the operation of the bearings. l have found that with a straight shaft bearing tightened so as to eliminate the last trace of vibration it was impossible to maintain lubricant between the bearing surfaces while if the bearings were constructed loose enough so that the lubricant would remain between the surfaces it was impossible to elminate vibration.l il also found the same diculties with the use of cone bearings, that is, if the bea-rings are made tight enough to eliminate all trace of vibration they cannot be lubricated by any method which I have been able to devise.

l attribute the high degree of success ci' this device primarily to the :tact that the structure is such that the bearings may be operated under a very high contact pres-` ateatro sure. While l have described my invention with respect to certain details or'construction by means of which the results described are readily carried out, it is to vbe understood that l dol not wish to be unduly limited theneby, other means of adjusting and supporting the bearings and other details of construction being possible without departingfrom the spirit or scope of my invention.

What i claim is:

The combination with a rotary shaft, of a stationary three piece support therefor comprising a central tubular member and a air of end members, each of said end mem ers having a part abutting its end of the tubular member, an inwardly faced bearing cone secured in each of said end members, a pair of outwardly faced bearing cones secured on opposite ends of said rota shaft, one of said cones having driving but sliding t -upon said shaft, a sleeve threaded upon the shaft between said cones and adapted tobe forced against one of said cones to slide it upon the shaft, tapered rollers between the cups and cones, the structure being such that the shaft may be bodily removed for adjustment of the slidabl'e cone thereon, and the whole replaced within the tubular support without altering the distance of adjustment ot the bearing parts from one another other than such alteration as was madeby the movement of the said slidable cone on the shaft.

ln witness whereof, l hereunto subscribe my name this th day of July, A. D 1916.

' CARL A.. PFANSTIEHJ. Witnesses:

E.. li/i. Conner, C. C. Swinnen. 

